Global Patent Index - EP 0775918 A3

EP 0775918 A3 20000628 - Transmission-reception system

Title (en)

Transmission-reception system

Title (de)

Sende- und Empfangssystem

Title (fr)

Système de transmission et réception

Publication

EP 0775918 A3 20000628 (EN)

Application

EP 96118717 A 19961121

Priority

JP 30413395 A 19951122

Abstract (en)

[origin: EP0775918A2] The invention relates to a transmission-reception system. A transponder receiver unit contained in the key bow of an ignition key has a power circuit that receivers, rectifies and smoothes the carrier wave signal transmitted together with a time reference signal and an enquiry signal from the transmission-reception ECU of a motor vehicle. A microcomputer in the transponder becomes active when the output voltage of the power circuit reaches a predetermined level or higher. When activated, the microcomputer measures the time length of the received reference time signal using the clock signal generated by an oscillation circuit, and calculates a ratio, as a correction coefficient, between the measured time length and a stored reference time value. The microcomputer decodes the enquiry signal while correcting the time information included in the time series pulse signal forming the enquiry signal, using the correction coefficient. <IMAGE>

IPC 1-7

G01S 13/02; E05B 49/00

IPC 8 full level

B60R 25/04 (2013.01); B60R 25/24 (2013.01); F02N 15/00 (2006.01); G01S 13/75 (2006.01); G07C 9/00 (2006.01); H04B 1/59 (2006.01); H04B 5/48 (2024.01); H04B 7/26 (2006.01); H04L 9/32 (2006.01); H04Q 9/00 (2006.01); H04Q 9/14 (2006.01); H04W 4/04 (2009.01); H04W 12/02 (2009.01)

CPC (source: EP KR US)

B60R 25/04 (2013.01 - EP US); G01S 13/758 (2013.01 - EP US); G07C 9/00309 (2013.01 - EP US); H04B 1/40 (2013.01 - KR); G07C 2009/00777 (2013.01 - EP US)

Citation (search report)

Designated contracting state (EPC)

DE FR GB

DOCDB simple family (publication)

EP 0775918 A2 19970528; EP 0775918 A3 20000628; JP H09142257 A 19970603; KR 100387140 B1 20030819; KR 970031411 A 19970626; US 5838254 A 19981117

DOCDB simple family (application)

EP 96118717 A 19961121; JP 30413395 A 19951122; KR 19960051502 A 19961101; US 75479996 A 19961121